Sewage Material in Coal Liquefaction

ABSTRACT

The present disclosure provides methods and systems for coal liquefaction using a sewage material. A method of obtaining a de-ashed coal extract includes exposing a coal to a sewage material in the presence of a coal-derived solvent to form a slurry, elevating the temperature of the slurry to facilitate liquefying the coal and liberating a volatile matter, and separating the insoluble components from the slurry to obtain a de-ashed coal extract, wherein the coal extract is suitable for downstream processing.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of the following provisionalapplications, each of which is hereby incorporated by reference in itsentirety:

U.S. Provisional Application No. 61/357,323, filed Jun. 22, 2010; andU.S. Provisional Application No. 61/357,332, filed Jun. 22, 2010.

This application is a continuation-in-part of the following U.S. patentapplications, each of which is incorporated by reference in itsentirety:

U.S. Non-Provisional application Ser. No. 11/897,059, filed Aug. 29,2007; and U.S. Non-Provisional application Ser. No. 11/805,737, filedMay 24, 2007.

This application is a continuation of the following U.S. patentapplications, each of which is incorporated by reference in itsentirety:

United States Non-Provisional Application Number 13/165,857, filed Jun.22, 2011.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to coal-to-liquid technology, andspecifically to a system and method for liquefying coal using solventsthat hydrogenate under mild conditions.

2. Description of Related Art

Coal-to-liquid technology refers to chemical processes that convertsolid coal into liquid fuels and chemicals. The hydrogen to carbon ratio(H/C, molar) of coal is about 0.8 while that of liquid fuels is about2.0. The main functions of the coal-to-liquid processes are breakage ofthe coal's molecular size and addition of hydrogen into coal, or inother words, destructive hydrogenation of coal. These processes aregenerally termed as coal liquefaction.

Coal liquefaction may occur by two different pathways: indirectliquefaction and direct liquefaction. The indirect method converts coalto hydrogen and carbon monoxide, and syngas by reacting coal with steamat high temperatures in an oxygen-starved combustion process. Directliquefaction includes reaction of coal with hydrogen in a manner thatcoal becomes liquid. However, direct coal liquefaction has beenhistorically carried out with hydrogen gas, which requires hightemperature and pressure. In an example, direct coal liquefaction mayinvolve temperatures in excess of 450° C. and 2000 psig pressure.

Tetralin has been used as a donor solvent. However, a large overpressureof hydrogen and high temperature is needed to transfer the hydrogen fromthe gas phase to naphthalene, which is produced when tetralin isdehydrogenated as it transfers hydrogen to coal molecules. Thus, in siture-hydrogenation during liquefaction can be rather costly.

In view of the limitations discussed above, there exists a need for amethod of coal liquefaction utilizing an inexpensively produced,effective hydrogen donor solvent to digest coal.

SUMMARY OF THE INVENTION

In an aspect, the present invention provides methods and systems forinexpensively producing an effective solvent to digest coal.Alternatively, the methods and systems may enhance the dissolutionability of heavy aromatic oils by the addition of a hydrogenated liquid.In an embodiment, the hydrogenated liquid may be partially or fullyhydrogenated vegetable oil. The present invention may also provide aprocess that may liquefy coal without the need to hydrogenate thesolvent. In embodiments, this may occur by the use of an additive thatmay contain hydrogen, which may result in de-polymerizing large coalmolecules, while also suppressing recombination; thus, resulting insmaller overall molecular distribution and creating a liquid.

In an aspect, a method of obtaining a de-ashed coal extract includesexposing a coal to a hydrogenated vegetable oil in the presence of acoal-derived solvent to form a slurry, elevating the temperature of theslurry to facilitate liquefying the coal and liberating a volatilematter, and separating the insoluble components from the slurry toobtain a de-ashed coal extract, wherein the coal extract is suitable fordownstream processing. Water liberated as a result of the elevatedtemperature may be captured and stored. Volatile matter may be condensedand recycled. The method may further include distilling the coal extractto obtain a pitch. The coal-derived solvent may be selected from a groupcomprising recycled liquefied coal, coal tar distillate, and coal tarpitch. The hydrogenated vegetable oil may have a vapor pressure of lessthan 1500 psi at temperatures less than 400 degrees Celsius. Separatingmay include at least one of centrifugation, filtration, decanting, andfloat separation. The hydrogenated vegetable oil may be at least one ofsoybean oil, peanut oil, canola oil, olive oil, other vegetable oil orcombination of at least two of these oils. The temperature may beelevated to between 300 degrees Celsius and 600 degrees Celsius. Themethod may further include agitating the slurry to facilitate liquefyingthe coal. The coal may be selected from one or more of a sub-bituminouscoal, lignite coal and an anthracite coal. The method may furtherinclude heating the insoluble components to liberate a volatile matterand an entrained solvent, blending the insoluble components with acalcareous material and roasting the blend in a kiln at a temperaturegreater than 1000 degrees Celsius to obtain a clinker, and grinding theclinker to obtain a cement. The method may further include distillingthe coal extract under vacuum to obtain a mesophase pitch with asoftening point in the range of 25 degrees Celsius to 160 degreesCelsius, wherein the mesophase pitch can be coked to obtain ananisotropic coke. The method may further include coking the pitch toobtain a coke. The coke may be at least one of an anisotropic coke, ametallurgical coke, a graphite coke, an anode coke, and a needle coke.The method may further include air blowing the pitch to crosslinkmolecules in the pitch, the air blowing of synthetic pitch used for atleast modifying a softening point and increasing coke yield.

In an aspect, a method of obtaining a de-ashed coal extract may includeexposing a coal to a petroleum crude to form a slurry, elevating thetemperature of the slurry to facilitate liquefying the coal andliberating a volatile matter, and separating the insoluble componentsfrom the slurry to obtain a de-ashed coal extract, wherein the coalextract is suitable for downstream processing. Petroleum crude may be atleast one of crude bitumen, oil sands crude and liquids containing atleast 20% of oil sands crude. The de-ached coal extract may be added toa pipeline of petroleum crude for delivery to a petroleum refinery.

In an aspect, a method of obtaining a de-ashed coal extract may includeexposing a coal to a rubber material in the presence of a coal-derivedsolvent to form a slurry, elevating the temperature of the slurry tofacilitate liquefying the coal and liberating a volatile matter, andseparating the insoluble components from the slurry to obtain a de-ashedcoal extract, wherein the coal extract is suitable for downstreamprocessing. The rubber material may be from a rubber tire.

In an aspect, a method of obtaining a de-ashed coal extract may includeexposing a coal to a sewage material in the presence of a coal-derivedsolvent to form a slurry, elevating the temperature of the slurry tofacilitate liquefying the coal and liberating a volatile matter, andseparating the insoluble components from the slurry to obtain a de-ashedcoal extract, wherein the coal extract is suitable for downstreamprocessing.

In an aspect, a method of obtaining a cement by-product of coalliquefaction may include exposing a coal to a hydrogenated vegetable oilin the presence of a coal-derived solvent to form a slurry, elevatingthe temperature of the slurry to facilitate liquefying the coal andliberating a volatile matter, separating the insoluble components fromthe slurry, heating the insoluble components to liberate a volatilematter and an entrained solvent, blending the insoluble components witha calcareous material and roasting the blend in a kiln at a temperaturegreater than 1000 degrees Celsius to obtain a clinker, and grinding theclinker to obtain a cement.

In an aspect, a method of obtaining a quinolone insoluble-free andash-free mesophase pitch may include exposing a coal to a hydrogenatedvegetable oil in the presence of a coal-derived solvent to form aslurry, elevating the temperature of the slurry to facilitate liquefyingthe coal and liberating a volatile matter, separating the insolublecomponents from the slurry to obtain a de-ashed coal extract that isquinoline insoluble-free, and distilling the coal extract under vacuumto obtain a mesophase pitch with a softening point in the range of 25degrees Celsius to 160 degrees Celsius, wherein the mesophase pitch canbe coked to obtain an anisotropic coke. A quinolone insoluble-free andash-free pitch may be obtained by the method.

In an aspect, a method of obtaining a high quality coke from a low rankcoal extract may include exposing a coal to a hydrogenated vegetable oilin the presence of a coal-derived solvent to form a slurry, elevatingthe temperature of the slurry to facilitate liquefying the coal andliberating a volatile matter, separating the insoluble components fromthe slurry to obtain a de-ashed coal extract that is quinolineinsoluble-free, distilling the coal extract under vacuum to obtain apitch with a suitable softening point, and coking the pitch to obtain acoke. The coke may be at least one of an anisotropic coke, ametallurgical coke, a graphite coke, an anode coke, and a needle coke.The method may further include air blowing the pitch to crosslinkmolecules in the pitch, the air blowing of synthetic pitch used for atleast modifying a softening point and increasing coke yield.

In an aspect, an apparatus for coking includes a coated coking drum thatreceives a pitch material, wherein the coking drum is coated with acoating comprising at least one of a chromium, an aluminum, a nickel, oran alloy thereof, a heater that heats the pitch material to a cokingtemperature, and a flash vessel that condenses a liberated volatilematter, wherein a coke formed in the apparatus is readily removable.

In another aspect, an apparatus for coking includes a coated coking drumthat receives a pitch material, wherein the coking drum is coated with acoating comprising at least one of a chromium, an aluminum, a nickel, oran alloy thereof, a heater that heats the pitch material to a cokingtemperature, a flash vessel that condenses liberated volatile matter,and a coated Archimedes screw, wherein the Archimedes screw is coatedwith a coating comprising at least one of a chromium, an aluminum, anickel, or an alloy thereof, wherein the Archimedes screw pushes thepitch through the coking drum as it is being coked, and a coke formed inthe apparatus is removed by the force of the Archimedes spiral.

In yet another aspect, an apparatus for coking may include a coatedcoking drum that receives a pitch material, wherein the coking drum iscoated with a coating comprising at least one of a chromium, analuminum, a nickel, or an alloy thereof, a heater that heats the pitchmaterial to a coking temperature, a flash vessel that condensesliberated volatile matter, and a coated plunger, wherein the plunger iscoated with a coating comprising at least one of a chromium, analuminum, a nickel, or an alloy thereof wherein a coke formed in theapparatus is removed by the force of the plunger being pushed or pulledthrough the coking drum.

In an aspect, a modular coal liquefaction system may include a reactorfor exposing a coal to a hydrogenated vegetable oil in the presence of acoal-derived solvent to form a slurry, a heater that elevates thetemperature of the slurry in the reactor to facilitate liquefying thecoal and liberating a volatile matter, and a centrifuge that separatesthe insoluble components from the slurry to obtain a de-ashed coalextract, wherein the coal extract is suitable for downstream processing,wherein the reactor, heater, and centrifuge are adapted to be modular.The system may further include a distillation column that distills thede-ashed coal extract to obtain a pitch. The system may further includea coker that cokes at least one of the de-ashed coal extract and thepitch to obtain a coke. The system may be adapted to be modularlydisposed on a rail car. The system may be adapted to be modularlydisposed on a semi-truck trailer.

In another aspect, a modular coal liquefaction system may include areactor for exposing a coal to a hydrogenated vegetable oil in thepresence of a coal-derived solvent to form a slurry, a heater thatelevates the temperature of the slurry in the reactor to facilitateliquefying the coal and liberating a volatile matter, a centrifuge thatseparates the insoluble components from the slurry to obtain a de-ashedcoal extract, wherein the coal extract is suitable for downstreamprocessing, a distillation column that distills the de-ashed coalextract to obtain a pitch, and a coker that cokes at least one of thede-ashed coal extract and the pitch to obtain a coke, wherein the cokercomprises a coated coking drum that receives the de-ashed coal extractor the pitch, wherein the coking drum is coated with a coatingcomprising at least one of a chromium, an aluminum, a nickel, or analloy thereof, wherein the reactor, heater, centrifuge, distillationcolumn, and coker are adapted to be modular. The system may be adaptedto be modularly disposed on a rail car. The system may be adapted to bemodularly disposed on a semi-truck trailer.

In an aspect, a coal liquefaction system includes a reactor for exposinga coal, to a hydrogenated vegetable oil in the presence of acoal-derived solvent to form a slurry, a heater that elevates thetemperature of the slurry in the reactor to facilitate liquefying thecoal and liberating a volatile matter, and a centrifuge that separatesthe insoluble components from the slurry to obtain a de-ashed coalextract, wherein the coal extract is suitable for downstream processing.The system may further include a distillation column that distills thede-ashed coal extract to obtain a pitch. The system may further includea coker that cokes at least one of the de-ashed coal extract and thepitch to obtain a coke. The coker includes a coated coking drum thatreceives the de-ashed coal extract or the pitch, wherein the coking drumis coated with a coating comprising at least one of a chromium, analuminum, a nickel, or an alloy thereof. The system may be adapted to bemodular. The system may be adapted to be modularly disposed on a railcar. The system may be adapted to be modularly disposed on a semi-trucktrailer.

In an aspect, a coal liquefaction system includes a reactor for exposinga coal to a hydrogenated vegetable oil in the presence of a coal-derivedsolvent to form a slurry, a heater that elevates the temperature of theslurry in the reactor to facilitate liquefying the coal and liberating avolatile matter, a centrifuge that separates the insoluble componentsfrom the slurry to obtain a de-ashed coal extract, wherein the coalextract is suitable for downstream processing, a distillation columnthat distills the de-ashed coal extract to obtain a pitch, and a cokerthat cokes at least one of the de-ashed coal extract and the pitch toobtain a coke, wherein the coker comprises a coated coking drum thatreceives the de-ashed coal extract or the pitch, wherein the coking drumis coated with a coating comprising at least one of a chromium, analuminum, a nickel, or an alloy thereof.

In another aspect of the invention, the methods and systems may producea slurry of coal liquids and undissolved coal particles. The slurry maybe further refined to produce a pitch, which may be considered a finalproduct or alternatively may be upgraded to produce lighter hydrocarbonsynthetic crude for fuels and chemicals. The present invention may alsoseek to remove sulfur from sulfur-containing hydrocarbon liquids such ascrude petroleum.

These and other systems, methods, objects, features, and advantages ofthe present invention will be apparent to those skilled in the art fromthe following detailed description of the preferred embodiment and thedrawings. All documents mentioned herein are hereby incorporated intheir entirety by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention and the following detailed description of certainembodiments thereof may be understood with reference to the followingfigures:

FIG. 1 illustrates an overview of a system for carrying out a coalliquefaction process, in accordance with an embodiment of the presentinvention.

FIG. 2 illustrates a flowchart illustrating a method of increasing theaverage molecular weight of a pitch product, in accordance with anembodiment of the present invention.

FIG. 3 illustrates a block flow diagram of an example of a processingsystem that may be used to produce synthetic pitch, in accordance withan embodiment of the present invention.

FIG. 4 is a chart depicting an example of coal conversion using varioussolvents in accordance with one embodiment.

FIG. 5 is a chart depicting an example of the benefits of hydrogenationof the feedstock solvent on coal conversion, in accordance with oneembodiment.

FIG. 6 depicts a process flow diagram for coal liquefaction.

FIG. 7 depicts an embodiment of the coal liquefaction system.

FIG. 8 depicts an embodiment of a process flow of a distillation column.

FIG. 9 depicts an embodiment of a process flow of a coker.

FIG. 10 depicts a method of a coal liquefaction process.

FIG. 11 depicts a method of a coal liquefaction process.

FIG. 12 depicts a method of a coal liquefaction process.

FIG. 13 depicts a method of a coal liquefaction process.

FIG. 14 depicts a method of obtaining a cement by-product of coalliquefaction.

FIG. 15 depicts a method of obtaining a quinolone insoluble-free andash-free mesophase pitch.

FIG. 16 depicts a method of obtaining a high quality coke from a lowrank coal extract.

FIG. 17 depicts a coated coker and coated plunger.

FIG. 18 depicts a mobile coal liquefaction unit.

Those of ordinary skill in the art will appreciate that the elements inthe figures are illustrated for simplicity and clarity and are notnecessarily drawn to scale. For example, the dimensions of some of theelements in the figures may be exaggerated, relative to other elements,in order to improve an understanding of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Detailed embodiments of the present invention are disclosed herein;however, it is to be understood that the disclosed embodiments aremerely exemplary of the invention, which may be embodied in variousforms. Therefore, specific structural and functional details disclosedherein are not to be interpreted as limiting, but merely as a basis forthe claims and as a representative basis for teaching one skilled in theart to variously employ the present invention in virtually anyappropriately detailed structure. Further, the terms and phrases usedherein are not intended to be limiting, but rather to provide anunderstandable description of the invention.

The terms “a” or “an,” as used herein, are defined as one or more thanone. The term “another,” as used herein, is defined as at least a secondor more. The terms “including” and/or “having”, as used herein, aredefined as comprising (i.e., open transition).

The present invention relates to coal solvents and more specifically toa method for inexpensively producing an effective partially or fullyhydrogenated solvent to digest coal, thereby producing a slurry of coalliquids and undissolved coal particles. In an embodiment, the presentinvention may include three phases. The first phase may includeformation of a coal slurry and that may be treated in a reactor and maythen be centrifuged to obtain a centrate. The second phase may includedistillation of the centrate produced in the first phase. Thedistillation may result in formation of pitch that may be introduced toa coker in the third phase. In this phase, the pitch may be coked toobtain coke with different properties.

The present disclosure describes a process for coal liquefaction thatinvolves the mixing of ground coal, a coal tar distillate that has beenpurchased from a coke oven operator or distributor or collected fromprior runs of the process, and a hydrogen donor solvent to form aslurry. Most coal liquefaction was done previously with bituminous coal,but in contrast, the present disclosure describes the advantageous useof sub-bituminous and lignite coals and other low rank coals notpreviously considered suitable for liquefaction. It should be understoodthat the process described herein may be employed with any kind of coal.Coal liquefaction has previously been carried out with hydrogen gas,requiring high temperature and pressure, commonly at 450 C and 2000 psigpressure. In the Exxon donor process, hydrogenated naphthalene is usedas a proton donor. Naphthalene hydrogenation, and in siture-hydrogenation, requires high temperatures and high pressures. Thepresent disclosure describes the unexpected liquefaction resultsobtained using hydrogenated vegetable oil or partially hydrogenatedvegetable oil in combination with a coal tar distillate (CTD).Liquefaction can proceed without high temperature or applied pressurethat is usually required for liquefaction, however, any level oftemperature and pressure may be employed in the process. Also, it isrelatively easy and inexpensive to hydrogenate vegetable oil. Coal alsoliquefies without high temperature or pressure in pipeline crude oil,since pipeline crude has excess hydrogen. Coal also liquefies in CTDmixed with ground up rubber tires as the H-donor, lignin-containingsewage sludge, and other hydrogen donor solvents further describedherein.

The slurry is heated at ambient pressure in a reactor to drive offwater. At this stage in the process, the temperature may only be raisedhigh enough to boil off water. Water is flashed off when the pressurebuilds up in the reactor and can optionally be collected and stored.Many cycles may be needed to remove substantially all of the water.Alternatively, the coal may first be dried. After a few cycles of waterevaporation, the reactor is brought up to temperature for the thermalbreakdown of the coal molecules. The fracturing of the large coalmolecules commonly occurs through the formation of radicals. As radicalsform, the hydrogen donor solvents donate a hydrogen to stabilize theradical, thus stabilizing the liquid form. As aromatic sites getsaturated, the coal liquid becomes more and more aliphatic. While thehydrogen donor solvent may be involved in stabilization of thermallygenerated radicals, it may also be involved in bond cleavage. Thus, theprocess may actually be improved by having only partially hydrogenatedsolvents because once all of the radical sites are filled, they will notbe re-cleaved. The process liberates volatiles, which can be fed backinto the process as “CTD starting material”. There are changes thatoccur in the chemical composition of the recycled CTD. More dissolvedcoal molecules replace some of the original molecules so the solventbecomes more compatible with the dissolving coal as the CTD is beingreused. Indeed, any volatiles liberated throughout the process may berecovered and recycled as starting material.

The resultant coal extract is centrifuged, or otherwise subjected to aseparation process, to de-ash it. The solid ash, or tails, can berecovered from the centrifuge and processed to eventually obtain acement, which will be further described below. The centrate is collectedand can immediately be subjected to petroleum-type refining processes toobtain fuels. Alternatively, it can be distilled. Partial distillationresults in a heavy crude-like substance, which can be further refinedusing petroleum-type refining processes. Further distillation results inpitch similar to coal tar binder pitch, but without the quinolineinsoluble matter. Annealing at this distillation step alters theproperties of the resultant pitch. Pitch can be further processed in acoker, such as a delayed coker. Optionally, the pitch can be air blownto obtain coke with different properties.

In some embodiments, the coker may be coated with chrome, nickel,aluminum or alloys thereof to facilitate removal of the coke. Theplunger or worm gear of the coker may also be similarly coated tofacilitate coke removal. The coated coker is smaller than othercommercially available cokers, thus, CTL processes/plants with coke asthe end product may be miniaturized or mobilized. Carbon materials suchas coke stick to steel. It is difficult to separate coke from steel;however, coke does not stick to chrome or chrome alloys thereforecoating steel with chrome or chrome alloys permits separation of cokefrom the surface.

FIG. 1 illustrates a system 100 for carrying out a coal liquefactionprocess. The system 100 may include a coal liquefaction reactor 102(hereinafter referred to as reactor 102). The reactor 102 may be aclosed reactor. In an embodiment, the reactor 102 may be run in acontinuous mode, i.e., reactants may be continuously fed into thereactor 102 and may emerge as a continuous stream of products. Further,the reactor 102 may be run in a batch mode for carrying out a sequenceof different operations such as solids dissolution, product mixing,batch distillation, and the like. In an embodiment, the reactor 102 maybe configured with alkali columns for mitigating odor. For example, thereactor 102 may be provided with sodium hydroxide (NaOH) columns forabsorbing the odor.

Further, the reactor 102 may enable mixing various reactants such ascoal 104, a CTD 108, and an additive 110 to form a slurry in whichreactive dissolution of the coal 104 occurs to yield a coal extract.After liquefaction, the coal extract may be de-ashed. In an embodiment,the coal extract may be de-ashed by employing a separation process, suchas centrifugation, float separation, decanting, filtration, and thelike, to separate the extract into a heavy phase containing theinsoluble coal products and a light phase (hereinafter referred ascentrate) containing the soluble coal products. The centrate may berefined using typical petroleum refining processes to yieldtransportation fuels. Alternatively, the centrate may be distilled toyield a pitch that can be coked to yield high value coke products. Thepitch may also be refined using typical petroleum refining processes toyield transportation fuels.

In an embodiment, the coal 104 may be a low rank coal such assub-bituminous coal. Further, the low-rank coal products may be rich inhydrogen, possess higher oil to asphaltene ratios, and may be morealiphatic than the bituminous coal liquids. The present invention mayenable generation of high quality coke from low rank coals; however, itwill be evident to a person skilled in the art that the coal 104 may bebituminous, lignite, and the like.

In an embodiment, the coal 104 may be crushed to −20 mesh (800 microns)or smaller before combining the coal 104 with other reactants. Further,the CTD 108 may be obtained from a petroleum refinery, a coal tarrefinery, purchased from a coke oven operator or distributor, or thelike. Alternatively, the CTD 108 may be collected from prior cycles ofthe liquefaction processing in the system 100. In an embodiment, theadditive 110 may be a hydrogen donor solvent (H donor solvent). Inembodiments, the H donor solvent may be alternatively referred as aproton transfer agent.

In an embodiment, the additive 110 may be a partially or fullyhydrogenated vegetable oil (hereinafter alternatively referred to asHVO). The HVO may include, but is not limited to, corn, canola,sunflower, safflower, and olive. Since vegetable oils may be easilyhydrogenated, they may be preferred as the H donor solvent for use inthe system 100. In an embodiment, the partially hydrogenated vegetableoil may include one part of hydrogenated vegetable oil mixed with onepart of non-hydrogenated vegetable oil, or any other ratio thereof.Vegetable oils may be hydrogenated to a level of up to ten percenthydrogen by weight using lower pressure, lower temperature and shorterresidence time than hydrogensation of other solvents, such asnaphthalene. For example, soybean oil can be hydrogenated at a pressureof less than 200 psi, at a temperature less than 200° C., and aresidence time of 10 minutes or less. Hence, this process requires lessprocessing energy, since generation of high temperature and pressure isenergy-intensive. Moreover, hydrogenated vegetable oils are known fortheir overall economy and high boiling point, making them suitable foruse in processes to dissolve coal.

In embodiments, a plurality of hydrogenated solvents may be used for thecoal liquefaction process. The hydrogenated solvents may include, butare not limited to, pipeline crude oil, rubber tires, animal waste,anything with the potential of adding a proton to an aromatic orbreaking a chemical bond, horse manure, chicken manure, sewage sludge,lignin, any bio-waste with lignin, peanut oil, soybean oil, canola oil,olive oil or other vegetable oil, decalin, partially hydrogenated coaltar distillate, or partially hydrogenated petroleum distillate orpartially hydrogenated decant oil or recycle oil, Fisher-Tropsch liquid,methyl naphthalene, decahydronaphthalene, tetrahydronaphthalene, methylnaphthalene, creosote oil, coal tar pitch, asphalt pitch, gasificationtar, recycled motor oil, petroleum distillates, rubber, plastics,recycled plastics (e.g. polystyrenes), recycled rubber, biomassderivatives, liquefied coal, liquefied biomass, shale oil, liquefiedprocess gas, cacenaphthenes, di, tetra- and octahydroanthracenes,tetrahydroacenaphthenes and other derivatives of partially hydrogenatedaromatic compounds, petroleum distillates, petroleum catalytic crackerproducts, distillates of gasification tars, products from the pyrolysisof recycled hydrocarbons, and aromatic oil products obtained from thedistillation of shale oil or tar sands.

As mentioned herein, rubber tires may be used as an H donor solvent. Therubber tires may include about 40% carbon black by weight. When coal isdissolved using these rubber tires, this carbon black may becomequinoline insoluble and, therefore, the pitch obtained may be tuned tocommercially used pitches from coke ovens.

In an embodiment, lignin may be used as an H donor solvent. Lignin is anundigested, propylbenzene polymer found in mammal waste. Hydrogen lostdue to splitting of the polymer may be used as a hydrogen source. In anexample, when bacteria consume oxygen containing compounds from tertiarysewage sludge, the sludge is left with lignin. Thus, tertiary sewagesludge may be used in the coal liquefaction process.

In an embodiment, a blend of hydrogenated and non-hydrogenated solventsmay result in an improved yield. For example, during coal liquefaction,once a coal molecule breaks down into smaller pieces, proton transfermay take place. The smaller pieces of the coal molecule may gethydrogenated and may tend to become non-polar. Accordingly, thenon-polar coal molecules may get dissolved in the non-protonated form ofthe solvent.

In embodiments, the coal liquefaction process may proceed at a lowerpressure than is usually required for coal liquefaction e.g., 400 psig.In an embodiment of the present invention, the HVO may enable the coalliquefaction process to be run at lower temperature and lower pressurewith less hydrogen. In a scenario, the coal liquefaction process mayenable hydrogenation through the proton transfer agent at milderconditions when compared with the conditions of conventional protontransfer agents. For example, the coal liquefaction process may requireless extreme conditions to transfer hydrogen to vegetable oils ascompared to transfer of hydrogen to naphthalene. Consequently, it may beeasier to remove hydrogen from HVO and therefore, it may serve as abetter transfer agent than tetralin, for example.

In an example, hydrogenation of naphthalene may require high temperature(more than 300° C.) and high pressure (1000 psi or more). Further, thehydrogenation of naphthalene may require a long residence time (morethan 10 minutes). However, soybean oil may be hydrogenated at a pressureof less than 200 psi, at a temperature less than 200° C., and aresidence time of 10 minutes or less. Hence, this process may requireless processing energy as generation of high temperature and pressuremay be energy-intensive. Further, hydrogenated vegetable oils have highboiling points, thereby making them suitable for use in processes todissolve coal. In an embodiment, the hydrogenation of solvents for theliquefaction process may be achieved and/or enhanced at low temperatureand pressure by introducing hydrotreating catalysts such ascobalt-molybdenum catalyst, nickel-molybdenum catalyst, and the like.

The mass ratio of coal to total solvents may be about 1:2.5, 1:2, or thelike. In an embodiment, the mass ratio may be greater. The slurry asmentioned herein may be heated at an ambient pressure in the reactor 102to drive off water. At this stage in the process, the temperature mayonly be raised high enough to boil off water. Many cycles of the processmay be required for completely removing the water. In an alternativeembodiment, the coal 104 may be dried first. After a few cycles of waterevaporation, the reactor 102 may be brought up to a temperature forliquefaction. The thermal rupture of coal molecules may result in theproduction of unstable free radicals. In an embodiment, the protontransfer agent may prevent re-polymerization in the coal liquefactionprocess. The free radicals, as mentioned herein, may react with hydrogendonated by the H donor solvent present in the process to form stablespecies. In some embodiments, the H donor solvent may be capable ofengendering bond scission. Thus, the process may be improved by havingonly partially hydrogenated solvents, i.e., one part of the molecules insolution may be hydrogenated while the others are not.

Therefore, once all the radical sites are filled, they may not bere-cleaved. The process may liberate volatiles, which may be fed(recycled) into the process as a CTD starting material. In anembodiment, there may be changes that may occur in the chemicalcomposition of the recycled CTD. As more dissolved coal moleculesreplace some of the original molecules, the recycle solvent may becomemore compatible with the dissolving coal. In an embodiment, any volatileliberated throughout the process may be recovered and recycled as thestarting material. Further, the proton transfer agent, such as the HVO,may saturate aromatic site and may render the resultant liquid morealiphatic.

In an embodiment, pipeline crude oil may be used as the additive 110 inthe coal liquefaction process. Accordingly, the pipeline crude oil mayact as a solvent as well as a proton transfer agent, and in someembodiments, a hydrogenation agent may be added to the coal liquefactionmixture for enhancing the dissolution of coal in the pipeline crude oil.The hydrogenation agent may facilitate addition of hydrogen molecules tothe pipeline crude oil, thereby enabling molecules of the pipeline crudeoil to become less polar. The addition of hydrogen molecules mayincrease solubility of the pipeline crude oil molecules in the coalliquefaction mixture.

After separation of the extract into insoluble material and centrate,the centrate may be added directly into a pipeline of a refinery. In anexemplary embodiment, if properties of the centrate and the pipelinecrude oil match or nearly match, the centrate may be added directly backinto the pipeline.

In an embodiment, coal 104 may not dissolve in the coal liquefactionmixture, and thereby make the pipeline crude oil less aromatic. In anexample, some coals may be more aromatic and may dissolve in an aromaticsolvent mixture more readily. For example, based on the aromaticity ofthe pipeline crude oil, the highly aromatic coal such as bituminous coalmay not dissolve in the coal liquefaction mixture. Further, aliphaticcoals such as lignite may dissolve well in an aliphatic solvent.

In another embodiment, if the pipeline crude oil is heavily aromatic, aplasticizer may be required to reduce the pipeline crude oil'sviscosity. Therefore, the pipeline crude oil may flow with lessresistance in the pipeline of the refinery. In a scenario, if the coaldissolved in the mixture is less mature, then it may be expected toproduce more aliphatic or smaller and lighter molecules. In such ascenario, the dissolved coal may be distilled and returned to a sourceof the pipeline crude oil as substitute plasticizers. The distillate maymake transportation of heavy pipeline crude oil economic and viable. Inan embodiment, two or more feedstock solvents may be blended togetherfor tailoring the properties of the centrate.

Optionally, the coal liquefaction mixture may be agitated usingultrasound. The ultrasound technique may enable the coal 104 to dissolvein the H donor solvent. As mentioned herein, the CTD 108 may bepurchased or derived from prior cycles of the liquefaction process. Inan example, the CTD 108 may be formed by blending distillates from eachstep of the liquefaction process.

In an embodiment, the more recycled the CTD 108, the better itfunctions, as continuous recycling helps components of the CTD 108 reacha steady state. In an embodiment, the composition of the liquefactionmixture may be optimized. The original source of a CTD is coal tar thatmay be obtained from a coke oven. Coals that are coked are generallybituminous coals. Therefore, the molecules in the CTD are typically fromaromatic bituminous coal. In a first example, when this CTD and thebituminous coals are added, molecules may get exchanged between the CTDand the bituminous coals resulting in new CTD that may have the samecomposition.

In a second example, when the CTD (obtained from bituminous coal) isdissolved in lignite coals, its composition may change as the lignitecoals are aliphatic compounds. When the mixture of the lignite coals andthe CTD is distilled, the pitch obtained may be rich in bituminous coalsand the distillate may be rich in the lignite coals. Accordingly, therecycled CTD may change composition. Therefore, as the recycling of theCTD is repeated, the CTD may get richer in lignite coals. Finally, asteady state may be reached where the CTD may become an efficientsolvent for the lignite coals. Thus, recycling of the CTD may change itsdissolution properties.

The degree of aromaticity and the size of molecules in the CTD mayenable it to be used as a solvent. The CTD 108 may need to have highviscosity for dispersing coal 104 within it. High viscosity of the CTD108 may not let the coal 104 settle in the coal liquefaction mixture.The middle distillate cut from the coal tars from the coke oven mayprovide an especially useful CTD.

In an embodiment, a catalyst may be added to the entire process of coalliquefaction. The catalyst may lower the processing temperature orpressure and may also modify properties of the mixture. Examples of thecatalyst may include, but are not limited to, salts of iron, molybdenum,tin, and Fe₂S₃ optionally with a hydrogen pressure.

In an embodiment, the temperature of the coal liquefaction mixture inthe reactor may be raised for condensing or flashing out the water outof the mixture. In an embodiment, this may be done by using a condenserloop. For example, the temperature may be raised to about 150° C. for200 lbs of the mixture so that water 112 may be removed from themixture, as the water 112 may become supercritical at higher temperatureand may generate pressure that may be too high for the reactor 102.Accordingly, the water 112 may be removed from the mixture beforeraising the temperature for avoiding high pressure generation in thereactor 102. The water 112 may be removed from the mixture throughmultiple cycles of raising the temperature and condensing out the water.Further, the water 112 may be recovered.

Once the water has been removed, the temperature of the mixture may beraised to about 425-450° C. in order to facilitate liquefaction. Themixture may be kept at this temperature in the reactor 102 for about 10minutes to an hour or longer. The coal molecules may break apart at theheteroatomic linkages, and, in embodiments, form radical sites. Further,hydrogen released from the proton transfer agent may react with themixture and seal off the radical sites of the broken linkages. This mayreduce the size of coal molecule clusters and may form a liquid extract.The reaction mixture may be agitated, such as by using a stirrer, anultrasound technique, or the like. The solvent extraction need not beperformed under a hydrogen atmosphere, however, a hydrogen atmospheremay optionally be used in order to enhance the absorption of hydrogen.

The volatile material may be sent to a flash condenser of the reactor102 for converting the volatile material into a condensed material 114.The condensed material 114 may be used as a CTD in the coal liquefactionprocess. Further, the condensed material 114 may be light as compared tothe coal extract 118. The coal extract 118 may be sent to a holding tankof the reactor 102 for bringing down the temperature of the coal extract118 to about 150° C. In an embodiment, the coal extract 118 may beallowed to cool down with time. Alternatively, the coal extract 118 maybe cooled down by using a heat transfer loop.

The following example is meant to illustrate an exemplary embodiment ofthe present disclosure, and is not intended to limit the scope of theembodiments as described herein and as defined in the claims:Experiments were carried out with different solvents to determinewhether hydrogenation improved the apparent solubility of coal in eachsolvent. Solvents tried include carbon black base oil (“CBB”, a coal tardistillate obtained from Koppers), anthracene oil (“AO”, a coal tardistillate obtained from Reilly Industries), Maraflex®Oil (“MO”, amixture of petroleum distillates obtained from Marathon-Ashland),residual catalytic cracker slurry oil (“SO”, obtained fromMarathon-Ashland), and tetrahydronaphthalene (“tetralin”).

FIG. 4 depicts the coal conversion, in mass percent, obtained usingbituminous coal and the above-mentioned solvents. The crushed coal wasplaced into a sealed container along with the identified solvent at 400°C. for approximately one hour. Pressure within the sealed container wascontrolled by the vapor pressure of the solvent used. The coalconversion reported in the figure below is simply the fraction of coalmass that was converted from a solid to a liquid phase. These resultsindicate that tetralin, a known hydrogen donor solvent, is better thanthe other solvents in terms of coal conversion.

In order to determine whether hydrogenation can enhance the ability toextract coal in the liquid phase, three different hydrogenationconditions were established, as shown in Table 1.

TABLE 1 Solvent Hydrogenation Results Wt % H2 Hydrogenation Initial ColdH2 Run Description absorbed reactor T, ° C. Pressure (psig) CBBHydrogenation 0.10 275 500 Level 1 CBB Hydrogenation 0.14 350 500 Level2 CBB Hydrogenation 0.24 375 750 Level 3 Slurry Oil 0.24 375 750Hydrogenation Level 3 Maraflex Oil 0.24 375 750 Hydrogenation Level 3

Coal extraction using these hydrogenated solvents was performed in thesame manner as described previously. As shown in FIG. 5, coal conversionusing hydrogenated solvents from coal tar distillates (e.g., carbonblack base oil) is significantly improved as compared to the use ofnon-hydrogenated forms of those same solvents. In fact, the performancewas similar to that of tetralin.

Subsequently, experiments with bituminous coal and CBB L3 produced coalconversion of 90% at 425° C. This shows that hydrogenation ofhydrocarbon materials can produce an effective alternative to tetralin,a much more expensive solvent that generally cannot be economicallyincorporated into the pitch product.

In an embodiment, the coal extract may be directed to a separationprocess via gravity flow. Alternatively, pressure may be applied to thesystem to drive the extract to the separation process.

Further, the coal extract 118 may be subjected to a separation processto de-ash the coal extract 118, such as centrifugation, filtration,decanting, float separation, or the like. The separation process mayseparate insoluble material from the extract, such as ash andquinolone-insoluble materials. In an embodiment, the coal extract 118may be de-ashed by using a centrifuge 120. The centrifuge may be a bowlcentrifuge, a scroll decanter centrifuge, or the like. The scrolldecanter centrifuge may include a conical rotating member that may stripthe solids at a given gravitational force. In the above-mentionedprocesses, the temperature may need to be kept low such that theviscosity may be less than 100 centipoise. In an embodiment, the extractmay have a viscosity below 200 centipoise at an operating temperature ofabout 140° C. of the centrifuge 120. Preferably, the viscosity may bebelow 100 centipoise (closer to 40 centipoise) at 200° C. for use in thecentrifuge 120. In an embodiment, the centrifuge 120 may include acondenser (not shown) for collecting volatile materials.

The centrifugation process may result in solid ash or tails 122 andcentrate 124. The tails 122 may contain about 25-35% volatile materials.These volatile materials may be volatiles from the coal 104 or entrainedsolvent. Further, the tails 122 may include about 55% ash and about 15%fixed carbon. As a result of the centrifugation, some volatile materialmay be obtained, this volatile material may be baked and collected(collected volatile 128) and may be added to the recyclable CTD. Bakingthe tails may produce a solid cake that may include about 85% ash andabout 15% fixed carbon. In an embodiment, the ash may be asilicate/aluminate blend.

The solid cake may be mixed with limestone to achieve a 3:1 calcium tosilicate/aluminate ratio. This configuration may then be baked in a kilnat about 1400° C. At this temperature, the mixture may burn off thefixed carbon and may produce a clinker. In an embodiment, the clinkermay be produced by combining clays in the ash and calcium in thelimestone. The clinker may thereafter be ground to make cement.

In another embodiment, the ash may include metals and non-metals thatmay be separated from the centrate 124 during centrifugation. Theseseparated metals and non-metals may be reacted during clinker formationas insoluble salts of calcium or silicates, and finally may beincorporated into the cements. Accordingly, the present invention maynot produce any solid waste after the coal 104 is reacted. Further, thewaste material may be used for producing a value-added product.

Referring to FIG. 10, a method of obtaining a de-ashed coal extractincludes exposing a coal to a hydrogenated vegetable oil in the presenceof a coal-derived solvent to form a slurry 1002, elevating thetemperature of the slurry to facilitate liquefying the coal andliberating a volatile matter 1004, and separating the insolublecomponents from the slurry to obtain a de-ashed coal extract, whereinthe coal extract is suitable for downstream processing 1008. Waterliberated as a result of the elevated temperature may be captured andstored. Volatile matter may be condensed and recycled. The method mayfurther include distilling the coal extract to obtain a pitch. Thecoal-derived solvent may be selected from a group comprising recycledliquefied coal, coal tar distillate, and coal tar pitch. Thehydrogenated vegetable oil may have a vapor pressure of less than 1500psi at temperatures less than 400 degrees Celsius. Separating mayinclude at least one of centrifugation, filtration, decanting, and floatseparation. The hydrogenated vegetable oil may be at least one ofsoybean oil, peanut oil, canola oil, olive oil, other vegetable oil orcombination of at least two of these oils. The temperature may beelevated to between 300 degrees Celsius and 600 degrees Celsius. Themethod may further include agitating the slurry to facilitate liquefyingthe coal. The coal may be selected from one or more of a sub-bituminouscoal, lignite coal and an anthracite coal.

Referring to FIG. 11, a method of obtaining a de-ashed coal extract mayinclude exposing a coal to a petroleum crude to form a slurry 1102,elevating the temperature of the slurry to facilitate liquefying thecoal and liberating a volatile matter 1104, and separating the insolublecomponents from the slurry to obtain a de-ashed coal extract, whereinthe coal extract is suitable for downstream processing 1108. Petroleumcrude may be at least one of crude bitumen, oil sands crude and liquidscontaining at least 20% of oil sands crude. The de-ashed coal extractmay be added to a pipeline of petroleum crude for delivery to apetroleum refinery.

Referring to FIG. 12, a method of obtaining a de-ashed coal extract mayinclude exposing a coal to a rubber material in the presence of acoal-derived solvent to form a slurry 1202, elevating the temperature ofthe slurry to facilitate liquefying the coal and liberating a volatilematter 1204, and separating the insoluble components from the slurry toobtain a de-ashed coal extract, wherein the coal extract is suitable fordownstream processing 1208. The rubber material may be from a rubbertire.

Referring to FIG. 13, a method of obtaining a de-ashed coal extract mayinclude exposing a coal to a sewage material in the presence of acoal-derived solvent to form a slurry 1302, elevating the temperature ofthe slurry to facilitate liquefying the coal and liberating a volatilematter 1304, and separating the insoluble components from the slurry toobtain a de-ashed coal extract, wherein the coal extract is suitable fordownstream processing 1308.

Referring to FIG. 14, a method of obtaining a cement by-product of coalliquefaction may include exposing a coal to a hydrogenated vegetable oilin the presence of a coal-derived solvent to form a slurry 1402,elevating the temperature of the slurry to facilitate liquefying thecoal and liberating a volatile matter 1404, separating the insolublecomponents from the slurry 1408, heating the insoluble components toliberate a volatile matter and an entrained solvent 1410, blending theinsoluble components with a calcareous material and roasting the blendin a kiln at a temperature greater than 1000 degrees Celsius to obtain aclinker 1412, and grinding the clinker to obtain a cement 1414.

Further, the centrate 124 may be collected and immediately subjected toa petroleum-type refining process for producing transportation fuels. Inan alternative embodiment, the centrate 124 may be further refined viadistillation, coking, or other processes. In an embodiment, the centrate124 may flow or may otherwise be introduced to a distillation column 130such as a multi-tray distillation column, a Wiped Film Evaporator (WFE),or the like. For example, the WFE may include features such as vacuumdistillation, short residence time, and a highly agitated thin film offeed product on a heated surface. These features may make the WFEsuitable for handling heat-sensitive and viscous materials.

Further, the centrate 124 may be distilled either under vacuum oratmospheric pressure. While carrying out the distillation underatmospheric pressure, temperature may need to be increased to distillsome of the volatiles. However, at high temperature, other components ofthe distillation mixture may get coked or cross-linked. Therefore, thedistillation column 130 may carry out the distillation process undervacuum. Since the centrate 124 contains no quinolone-insoluble matter orash, it is possible to obtain a pitch after processing the centrate.Distilling the centrate may result in a tailoring of the softeningpoint, a difference in coke yield, or changes in other properties. Forexample, in some embodiments, distillation results in the pitchsoftening at about 109° C. The pitch 132 may start to coke at highertemperatures, such as above 400° C.

In an embodiment, the centrate 124 may be distilled to obtain a pitch132 similar to coal tar binder pitch. In embodiments, the pitch 132 maybe alternatively referred to as synthetic pitch. Further, the pitch 132may not include any solvent or any insoluble material in it.

Additionally, the distillation process may remove some of the volatilespresent in the centrate 124. In an embodiment, partial distillation ofthe centrate 124 may result in a heavy crude-like substance that mayfurther be refined using the petroleum-type refining process. The heavycrude-like substance may be either produced directly from the distillateor by coking the pitch 132. In addition, the volatiles (that may beobtained from the distillation column 130) may be condensed to formliquids. The condensed volatiles 134 may be used as substitute crude oras solvent for additional executions of the coal liquefaction process.In embodiments, the volatiles may be plasticizers that may be added toincrease the fluidity of a material.

The pitch 132 may be blended with other binder pitches so that thequalities are closer to a coal tar binder pitch. In an embodiment, whenrubber tires are used as a liquefaction agent, carbon black obtainedfrom the rubber tires may be incorporated into the pitch 132 and theresultant product may be similar to the conventional coal tar pitchbinders.

It will be evident to a person skilled in the art that binder pitch maynot be a usual product from direct coal liquefaction because there istypically still quinolone insoluble material in coal extract from priorart coal liquefaction processes. However, in the present disclosure, theextract 118 obtained from the reactor 102 is quinolone insoluble-freebecause of the separation step employed in the process. For example,centrifugation may separate the quinoline insoluble material from theextract. In embodiments, the Residual Oil Supercritical Extraction(ROSE) technique may be used for de-ashing liquefied coals

Distillation may liberate low-boiling point species, including excesssolvent (particularly any additional solvents employed). A purified,synthetic pitch may be collected (e.g., such as in a collection drum).This pitch may have enhanced aromaticity, increased softening point,increased cross-linking reactivity, and increased carbon coking valuecompared to the pitch properties prior to distillation. Upon cooling toa temperature below about 110° C., the resultant pitch generallysolidifies. The pitch thus produced can have properties making itsuitable for use as a binder pitch. In some embodiments, the pitch maybe used either for carbon anodes for Hall Heroult cells for aluminumsmelting, for graphite electrodes for electric arc furnaces, or forother purposes. The pitch produced in accordance with the embodimentsmay also be used for other purposes, such as, but not limited to, animpregnation pitch used to produce carbon composites, as well as fiberspinning pitch used to produce carbon fibers. The low-boiling pointspecies removed in the solvent separation unit may be optionallyrecycled back to be blended with the solvents used for subsequent coalliquefaction, with or without an additional hydrogenation cycle.

In some embodiments, distillation yields light distillates, middledistillates, and heavy distillates. One use of the light distillates maybe to obtain transportation fuels after subsequent refining, which canbe accomplished using petroleum refining techniques and systems. One useof the middle distillates may be to recycle back as a starting materialin the coal liquefaction process. One use of the heavy distillates maybe to coke them to obtain high quality cokes.

In embodiments, an annealing process may take place in the distillationcolumn 130 that may alter the properties of a resultant pitch. Further,it may be evident to those skilled in the art that annealing may only beeffective in pitches that may not include quinoline insoluble material.The pitch 132 may include large discotic molecular clusters displayingafused, flat or polycyclic aromatic ring structure. At low viscosity,the clusters flow and are attracted to other clusters by the electronsin the Pi cloud associated with each of the ring clusters, thus causingthe aromatic rings to stack. As the association becomes stronger, theyform ordered structures, and eventually, a large domain of a liquidcrystal called mesophase pitch. The mesophase pitch is denser than theparent pitch so it settles to the bottom of the distillation column. Inone embodiment, upon delayed coking, this liquid crystal phase producesa very anisotropic coke, needle coke, needed for the manufacture ofanisotropic graphite. Other cokes may likewise be obtained.

In an embodiment, the degree of annealing may change the degree ofassociation between the clusters. The annealing process may facilitateproduction of an improved pitch. Further, annealing process variablesmay be modified to modify the anisotropy. In an exemplary embodiment,annealing may be carried out at different temperatures and anisotropymay change based on the annealing.—Higher anisotropic cokes with betterconducting properties may be produced as a result of modification in theannealing process. For example, anode coke is only slightly anisotropicwhile needle coke or graphite coke are highly anisotropic. Other processvariables include: temperature, pressure, residence time, gas flow rate,and the like. In embodiments, the pitch 132 may facilitate production ofan impregnating pitch, a graphite pitch, an anode pitch, and the like.In some embodiments, two or more feedstock solvents may be blendedtogether to tailor the properties of the synthetic pitch 132. By way ofexample, for binder and impregnating pitch applications, Table 2 belowprovides exemplary properties that may be achieved with embodiments ofthe methods of the present disclosure.

TABLE 2 Pitch Properties Binder Pitch Impregnating Pitch Softening Pt.100-120° C. 75-150° C. Viscosity <20 poise @ 160° C. <50 cps @ 225° C.Flash Pt. ≧200° C. ≧270° C. Coking value (wt %) 50-60 40-50

In an embodiment, the pitch may be hydrogenated, such as under hydrogenpressure, to produce an improved mesophase pitch upon annealing. Thehydrogenated pitch is less reactive. Such improved mesophase pitchesresult in improved cokes, such as needle coke, with respect to thedegree of anisotropy upon coking.

Referring to FIG. 15, a method of obtaining a quinolone insoluble-freeand ash-free mesophase pitch may include exposing a coal to ahydrogenated vegetable oil in the presence of a coal-derived solvent toform a slurry 1502, elevating the temperature of the slurry tofacilitate liquefying the coal and liberating a volatile matter 1504,separating the insoluble components from the slurry to obtain a de-ashedcoal extract that is quinoline insoluble-free 1508, and distilling thecoal extract under vacuum to obtain a mesophase pitch with a softeningpoint in the range of 25 degrees Celsius to 160 degrees Celsius, whereinthe mesophase pitch can be coked to obtain an anisotropic coke 1510. Aquinolone insoluble-free and ash-free pitch may be obtained by themethod.

In an embodiment, optionally, the synthetic pitch 132 may be air blown.FIG. 2 illustrates a method 200 of increasing the average molecularweight of a pitch, in accordance with an embodiment of the presentinvention. The method 200 may start at step 202. At step 204, the pitchmay be distilled for separating lighter and heavier molecule fractions.Further, at step 208, the pitch may be air blown to cross-link theheavier molecules. In embodiments, air blowing of the synthetic pitchmay be used to cross-link hydrocarbons and solvent molecules that mayresult in modifying the softening point and increasing the coke yield.The cross-linking may facilitate an increase in the average molecularweight of the pitch as shown in step 210. At step 212, a potentialprecursor for anode grade coke, needle coke, and the like may becreated. The anode grade coke may be slightly anisotropic coke and theneedle coke may be highly anisotropic coke. The method 200 terminates at214. In an embodiment, a product produced by the process includes ahighly anisotropic (rod-like) coke, which may be of a particular longrange order or crystallinity.

In embodiments, if air blowing is done prior to removing the lightfractions from the pitch 132, the resultant pitch may produce anisotropic coke that may be unsuitable for anode grade coke, needle coke,and the like. Further, air blowing of the pitch 132 may be performed ata temperature between 250° C. and 450° C., 70° C. and 500° C., and thelike. In an example, to accomplish this, air may be bubbled through atube that may be inserted in a tank containing the pitch 132. In analternative embodiment, a sparger may be used for mixing air and thepitch 132. In embodiments, the pitch 132 may be further treated throughvarious downstream processes such as hydrothermal cracking,hydrodealkylation, delayed coking, hydrodesulphurization, steamcracking, catalytic cracking, and other refining techniques.

Referring to FIG. 16, a method of obtaining a high quality coke from alow rank coal extract may include exposing a coal to a hydrogenatedvegetable oil in the presence of a coal-derived solvent to form a slurry1602, elevating the temperature of the slurry to facilitate liquefyingthe coal and liberating a volatile matter 1604, separating the insolublecomponents from the slurry to obtain a de-ashed coal extract that isquinoline insoluble-free 1608, distilling the coal extract under vacuumto obtain a pitch with a suitable softening point 1610, and coking thepitch to obtain a coke 1612. The coke may be at least one of ananisotropic coke, a metallurgical coke, a graphite coke, an anode coke,and a needle coke. The method may further include air blowing the pitchto crosslink molecules in the pitch, the air blowing of synthetic pitchused for at least modifying a softening point and increasing coke yield.

Referring to FIG. 7, an embodiment of the coal liquefaction system isdepicted. A hydrogen donor solvent 702 is mixed with coal and istransported to a reactor 704 for liquefaction. After liquefaction, thecoal is either pumped or flows by gravity to a centrifuge 708. Oneproduct from centrifugation may be gasifier fuel, which may be utilized710 in the process to generate heat. The centrate is transported to adistillation column 712. Distillation results in separation ofcomponents of the centrate based on differences in boiling points.Depicted here are multiple components separated from the centrate,including pitches, light distillates, middle distillates, and gases. Inthis embodiment, the middle distillate is recycled 714 back into theprocess. Thus, the system is closed loop. Additionally, no CO₂ isgenerated. Pitches may be transported to a delayed coker for coking. Thecentrate and/or the distillates may be transported to a petroleumrefinery for processing to fuels, such as transportation fuels or otherhydrocarbon products.

The coal liquefaction process may be continuous or batch. For example,coal may be continually conveyed into the reactor, the coal extract maybe continuously pumped into the centrifuge or may flow continuously bygravity, a continuous use centrifuge may be used such as a scrolldecanter, the centrate may continuously be pumped from the output of thecentrifuge to the distillation column, and the pitches may continuouslybe siphoned off or pumped from the distillation column to a coker. Usinga coated coker system described later herein, the coker may also beoperated continuously to remove coke from the coking drum as it isformed.

In an embodiment, the system for coal liquefaction may be located near acoal mine so that transport of the coal is minimized. Alternatively,coal may be transported to the system via boat, truck, rail, or thelike. The coal may be pre-treated prior to liquefaction. For example,the coal may be dried using a hot air furnace, microwave treatment, orthe like. Other pre-treatments may also be used, such as exposure tocalcium, methanol/HCl, swelling solvents such as ethanol, THF, andtetrabutyammonium hydroxide (TBAH), steam, crushing, grinding,pulverization, and others.

In an embodiment, the system for coal liquefaction may be modular andsized to be disposed in a mobile unit, such as one or more rail cars,one or more semi-truck trailers, and the like. For example, andreferring to FIG. 18, an exploded view of a semi-truck trailer carryingthe system for coal liquefaction, including a distillation column,coker, and furnace, is depicted. It should be understood that not allembodiments of the modular/mobile unit will include all of thecomponents depicted in FIG. 18. In an embodiment, a modular coalliquefaction system may include a reactor for exposing a coal to ahydrogenated vegetable oil in the presence of a coal-derived solvent toform a slurry, a heater that elevates the temperature of the slurry inthe reactor to facilitate liquefying the coal and liberating a volatilematter, and a centrifuge that separates the insoluble components fromthe slurry to obtain a de-ashed coal extract, wherein the coal extractis suitable for downstream processing, wherein the reactor, heater, andcentrifuge are adapted to be modular. The system may further include adistillation column that distills the de-ashed coal extract to obtain apitch. The system may further include a coker that cokes at least one ofthe de-ashed coal extract and the pitch to obtain a coke. The system maybe adapted to be modularly disposed on a rail car. The system may beadapted to be modularly disposed on a semi-truck trailer. In anotherembodiment, a modular coal liquefaction system may include a reactor forexposing a coal to a hydrogenated vegetable oil in the presence of acoal-derived solvent to form a slurry, a heater that elevates thetemperature of the slurry in the reactor to facilitate liquefying thecoal and liberating a volatile matter, a centrifuge that separates theinsoluble components from the slurry to obtain a de-ashed coal extract,wherein the coal extract is suitable for downstream processing, adistillation column that distills the de-ashed coal extract to obtain apitch, and a coker that cokes at least one of the de-ashed coal extractand the pitch to obtain a coke, wherein the coker comprises a coatedcoking drum that receives the de-ashed coal extract or the pitch,wherein the coking drum is coated with a coating comprising at least oneof a chromium, an aluminum, a nickel, or an alloy thereof, wherein thereactor, heater, centrifuge, distillation column, and coker are adaptedto be modular. The system may be adapted to be modularly disposed on arail car. The system may be adapted to be modularly disposed on asemi-truck trailer.

The pitch 132 obtained from the distillation column 130 may be pumpeddirectly into a coke producing device 138 such as a coker, a cokebattery oven, and the like at a given temperature to instantaneouslyturn the pitch 132 into coke. This process may also be known as delayedcoking. Delayed coking may use lower temperatures and a longer residencetime than traditional coking and may produce both solid cokes as well asliquid or gaseous material.

In an embodiment, the pitch 132 may be coked or delay coked in a cokebattery oven (hereinafter referred to as coke oven). Coking may driveoff volatile gases. Further, the chemical function of the pitch 132 maychange as a function of time. In embodiments, various parameters of thecoker 138 may be varied as per the requirement. Examples of theparameters may include, but are not limited to, ramp rate, pressure,temperature, gases added in steam, addition of nitrogen, addition ofair, and the like.

For example, during the process, the pressure within the coker 138 maybe increased above 50 lbs (the pressure that is generally used forcoking) to change the bulk density of the pitch 132. Further, the pitch132 may be treated at higher temperatures such as between 400° C. and600° C. At such higher temperatures, lighter molecules may be liberatedfrom the pitch 132 in the form of gas or condensable vapors. Once thegases are released from the pitch 132, a solid non-melting residue maybe obtained. In some embodiments, the residue may mostly contain carbonand may be referred to as green coke. When the pitch 132 is baked at500° C., discotic molecules may enable formation of coke as stackedcrystals. In embodiments, different types of binder pitches may resultin formation of cokes of different properties.

The coke may contain aromatic hydrocarbons and may become moreanisotropic upon heating, such as at a temperature of 1000° C.-1400° C.to produce calcined coke, such as anode grade coke, needle grade coke,and metallurgical coke. Calcination of green coke may reduce the overallweight by about 5%, but at the same time it may make the coke stronger.In embodiments, gases that may be removed during calcination may includeabout 85% hydrogen gas.

Coke calcining is a process wherein the coke may be thermally upgradedto remove associated moisture and volatile combustion matter (VCM). Thecalcining process may also improve critical physical properties, such aselectrical conductivity, real density, oxidation characteristics, andthe like. Further, the calcining process may be a time-temperaturefunction with control variables such as heating rate, VCM/air ratio,calcination temperature, and the like. To obtain the calcined cokeproperties required by the carbon and graphite industries, the coke 140may be subjected to temperatures of 1000° C.-1400° C. to refine itscrystalline structure. The final quality of the calcined coke may bedirectly related to the specific characteristics and quality of the cokefed to the coker or calciner.

However, the supply of good quality coking coal is declining, so much sothat coking coals or metallurgical coals may be mined from seams as lowas 28 inches. The present invention may enable coking of non-cakingcoals such as sub-bituminous and lignite coals, whose availability isimmense. These non-caking coals are referred to as coal that may charand may not agglomerate to produce coke.

In embodiments, the coke 140 may not be crystalline; however, the coke140 may have long-range order of positioning of molecules. In anexample, graphite is anisotropic as opposed to a cube, which isisotropic.

The degree of the long-range order may modify the reflected light. Themore anisotropic the coke is, the more rod-like it is. For example,graphite may be hexagonal on one side and may be needle like on anotherside. In embodiments, anisotropy of the coke 140 may be proportional tothe value of the coke 140. Referring to graphite, carbon molecules inthe graphite may arrange themselves into a lattice structure, which mayallow free movement of electrons, thereby making graphite a goodconductor.

In embodiments, the pitch 132 may be used for preparing isotropic coke.The isotropic coke may be ground to make isotropic graphite (alsoreferred to as nuclear graphite). As a bulk property, the nucleargraphite may be isotropic and may not contain any ash.

In an embodiment, the coal 104 and the pitch 132 may be admixed in thecoker 138 for delayed coking or may be mixed with petroleum resids.

In embodiments, the tails 124 obtained from the centrifugation processmay include mineral matter that may be insoluble. The tails 124 mayeither be clinkered for conversion into cement or the tails 124containing the mineral matter may be heated in the presence of air to atemperature exceeding 1000° C. The heat treatment may completely oxidizeand melt the mineral matter present in the tails 124 and may form aslag.

Conventionally, a method for removing sulfur from sulfur-containinghydrocarbon liquids such as crude petroleum or coal extract may bedescribed as hydrodesulfurization. This process may involve exposing thehydrocarbon liquid to a high temperature pressurized hydrogen gas in thepresence of a catalyst. The result may be the formation of hydrogensulfide, which may be removed by dissolving the hydrogen sulfide inwater. In embodiments, the present invention may provide a method forproducing reduced sulfur hydrocarbon liquids. The present disclosuredescribes the use of a hydrogenated liquid such as HVO for removingsulfur from crude petroleum liquids. The HVO may be placed in a reactorand mixed with the crude petroleum liquids. Further, this blend may beheated at about 400° C.

In embodiments, the reactor is typically not pressurized with a gas.However, the vapor pressure of constituents in the blend may result inraising the reactor pressure to about 1000 psig. As a result, sulfurfrom the crude petroleum liquids may react with HVO to form hydrogensulfide, which may be removed as a vapor, leaving behind a blend ofhydrocarbons with low sulfur content. The resultant blend of vegetableoil and petroleum may be further refined with conventional refiningprocesses.

In an exemplary embodiment, graphite may be formed from the coke 140 andthe pitch 132. The coke 140 and the pitch 132 may be extruded throughholes of an oven along with highly viscous material to enable formationof an electrode. The electrode may be treated with gas that may bepassed through channels for again forming coke. This coke may be mixedwith impregnation pitch and may be impregnated into the holes of theelectrode. The impregnation may take place under application ofpressure. Further, the oven may bake the blend of coke and theimpregnation pitch. The resulting product may be taken through the sameprocedure, until a required density of the resulting product may beachieved. Such a product may be referred to as greenware. Further,electrodes may be added to the greenware and it may be heated to about2800° C. The heating may facilitate ordering of the discotic moleculesto obtain graphite.

In embodiments, the mesophase pitch may be extruded and graphitized byheat treatment, which may result in the formation of carbon fiberssimilar to human hair in dimension. The heat-treatedmesophase-pitch-derived carbon fibers may have high Young's modulus andhigh thermal conductivity. In an embodiment, the mesophase pitch mayhave high surface tension that may enable the mesophase pitch to stickto itself and thus, may differentiate it from the binder pitch.

In embodiments, only 40% of crude oil may include ingredients that maybe useful for the production of high-quality fuels. The remainingcomponents of crude oil may be heavy, poor performing fuels. These heavyfuels may be converted to usable transportation fuels through cracking.In an example, hydrogenated vegetable oil and crude oil may be treatedat high pressure and temperature in the presence of a catalyst. The highpressure and high temperature may facilitate hydrogen from the HVO to becombined with the crude oil. The combined influences of the catalyst,pressure, and heat may cause the hydrogen and the hydrocarbon moleculesto split. The hydrogen atoms may immediately combine with thehydrocarbons and form a light oil. Accordingly, hydrogenation may enablerecovery of gasoline from the crude oil.

The ingredients of the carbon-based fuel type materials may beclassified by solubility fractions. For example, oils may be known asthat portion of the fluid that may be soluble in cyclohexane. Asphalteneare those materials that may be insoluble in cyclohexane, but may besoluble in tetrahydrofuran. Further, pre-asphaltenes are materials thatmay be insoluble in both hexane and tetrahydrofuran. Likewise, pitchesmay be classified based on their solubility. In an example, toluenesoluble pitches may be light. Quinoline insoluble pitches may preventformation of mesophase. These pitches may include fixed carbon or carbonblack additives.

In embodiments, coal liquids may be blended with 10-95% alcohol tocreate a motor fuel with high octane rating and compatible combustionkinetics. Further, coal liquids are highly soluble in alcohol. Moreover,the high energy density of coal liquids may act to increase the energydensity of the blend. The aromatic content of coal liquids may enablethe blend to be compatible with polymer seals. In addition, although thecoal liquids are inherently slow burning, they are combusted morerapidly in the presence of a combusting alcohol. Hence, the combinationof coal liquids and ethanol may be favorable as compared to eithercomponent used in its pure state or blended with gasoline. Therefore,CE-85, which may include 85% ethanol and 15% coal liquids, may be soughtas non-petroleum derived motor fuel.

In embodiments, Fischer-Tropsch liquids may be used in place of thealcohol, while direct-liquefied coal liquids may be used as blendingagents. For example, Fischer-Tropsch liquids may be blended with coalliquids, including petroleum derivatives optionally. The Fischer-Tropschprocess may facilitate reaction of methane or gasified coal with air inthe presence of a catalyst to create synthesis gas, which may be amixture of carbon monoxide and hydrogen. Using another catalyst, thesynthesis gas may then be converted to a mixture of liquid hydrocarbons.The second catalyst may be an iron or cobalt-based commercial catalyst.The present disclosure may not involve the production of synthesis gasor conversion of synthesis to liquids, but instead may involveproduction of coal liquids via mild direct liquefaction that may then beblended with Fischer-Tropsch liquids to produce a substitute kerosene orjet fuel.

In embodiments, the coal 104 may be optionally dried prior to thepreparation of slurry. Pre-drying the coal 104 may result in enhancedsolubility of the coal 104. In an embodiment, the coal 104 may bepre-dried by using the waste heat of the reactor 102. In anotherembodiment, the coal 104 may be passed through a pre-drying zone forremoving moisture content of the coal 104 prior to its addition to theslurry. Pre-drying may include microwave treatment.

In embodiments, the solvent that may be used as the additive 110 may ormay not be hydrogenated. For example, the HVO, when used as a solvent,is already hydrogenated; however, other feedstock solvents, which maynot be hydrogenated, may also be used as the additive 110. The feedstocksolvents may include a hydrocarbon material that may have a softeningtemperature of less than about 200° C. and may contain at least 10%hydrocarbon species having a boiling point of over 350° C. When anon-hydrogenated solvent is used as the additive 110 in the slurry, thesolvent may be heated to a temperature of between 200° C. and about 500°C. in a hydrogen atmosphere. Further, a hydrogen pressure of up to about3000 prig may be applied such that the solvent of the extraction mixturehas absorbed hydrogen content (by weight) between 0.1% and 10%.

FIG. 3 illustrates a block flow diagram of a processing system 300 thatmay be used to produce pitch, in accordance with an embodiment of thepresent disclosure. The processing system 300 may include a tank reactor302. Hydrogen gas may be used to hydrogenate a portion of the feedstocksolvent. Optionally, a catalyst, such as, but not limited to, iron,cobalt, nickel, molybdenum, tin, salts of the foregoing metals, ormixtures of any of the foregoing, may also be added to the tank reactor302 to enhance the absorption of hydrogen by the feedstock solvent.Further, the feedstock solvent may be hydrogenated such that mass of thefeedstock solvent may be increased by up to several percent due to theabsorption of hydrogen.

After hydrogenation of at least a portion of the feedstock solvent, thehydrogenated solvent may be combined with one or more un-hydrogenatedfeedstock solvents, and/or one or more additional solvents (e.g.,tetralin). The solvent that has been removed from the pitch 132 may beblended with the feedstock solvent prior to being added to a second tankreactor in which the extraction takes place. This solvent recycle streammay include not only solvent (feedstock and additional solvent) andsolvent fractions removed from the pitch, but also other lighthydrocarbons extracted from the coal 104. As used herein, “lighthydrocarbons” may refer to materials having a boiling point lower thanabout 200° C., making them difficult to incorporate into the pitch 132intended to withstand de-volatilization until over 350° C. Recycling ofa portion of the solvent may permit dissolution of additional quantitiesof the coal 104. Alternatively, the portion of solvent removed from thepitch 132 may be considered a separate product (e.g., for use as anoctane enhancer).

Further, after hydrogenation, the feedstock solvent, optional additionalsolvent, and recycled solvent may be transferred to a tank reactor 304and may be combined with coal 104 (or other solids-containing material)to be extracted. The tank reactor 304 may be operated at ambientpressure. The extracts obtained from the tank reactor 304 may beintroduced to the centrifuge 120. The centrifugation and furtherdistillation of centrate through the distillation column 130 has beenexplained earlier and is not explained again for the sake of brevity.

Generally, a coker may be made up of a steel material. Coke may stick tothe sides of the coker and may be removed by scraping off the depositsusing water knives or other means. In embodiments, the coker may becoated with chrome to facilitate removal of coke. The chrome coating maybe erosion resistant and may be capable of withstanding heavy residualdeposits. In case of a chrome coating, the coke may be pushed out usinga plunger, a piston, and the like. Further, an auger may be built intocoker that may enable transporting the coke to the upper portions of thecoker. Additionally, a coating of aluminum or nickel may be used insteadof chrome as coke does not dissolve in aluminum or nickel.

In embodiments, the coker may be coated with materials such as chrome,aluminum, aluminum alloys, and nickel alloys. In an example, the cokermay be configured with a gear in the center for removing the coke. Inanother example, the coker may be configured with a hydraulic arm orplunger for facilitating removal of the coke. The gear and the plungermay also be coated with any of the materials mentioned above. In yetanother example, the coker may include an Archimedean spiral-based screw(also referred to as an Archimedes' screw) that may be used for drawingout coke from a reservoir of pitch. The coke may then be sent to acalciner. Further, in case of a continuous coker, the Archimedes' screwmay be used for continuously providing coke.

Further, the coated coker may be configured in a smaller size than othercommercially available cokers. Accordingly, the coated cokers mayfacilitate mobilization of coal liquefaction plants. In embodiments, themobile cokers may be implemented on one or more trucks or trailers orone or a series of rail cars, or the like.

In embodiments, odor may be produced in the reactor 102 due to presenceof toxic gases such as hydrogen sulfide, methylmercaptan, and mercaptan.The reactor 102 may include a column for mixing alkalis such as NaOH formitigating the odor. The alkali column may include Raschig rings thatmay be supported on a porous bed. The porous bed may provide moresurface area to the alkali column. Further, a showerhead may beconfigured at a top portion of the alkali column to be connected to thealkali reservoir. In an example, the reservoir may supply NaOH to theshowerhead for being shot inside the column. Further, the reservoir maysupply NaOH to the alkali column through a pump. The pump may allow theNaOH to flow from the reservoir to the showerhead. Further, a pipe forejecting the odor producing gases into the coker may be configured neara bottom surface of the column.

In use, the odor producing gases (hydrogen sulfide and mercaptan)flowing upwards may come in contact with the NaOH flowing downwards.When NaOH and the gases meet, hydrogen sulfide and mercaptan may becomesalts and may get captured in a solution. This conversion may continueuntil the solution may either be used in the process itself or may bediscarded later.

Although the present disclosure has been described in conjunction withthe production of liquid fuels and cokes in a delayed coker, othermethods and systems may be possible to carry out the present disclosurewithout limiting the spirit and scope of the present invention.

The conditions of the process may change with choice of coal to liquefyand desired endpoint. For example, and referring to FIG. 6, variouscoals may be liquefied by the process, such as regional coal types,dried coal, pulverized coal, microwaved coal, ground coal, bituminous,subbituminous, anthracite, lignite, brown coal, and the like. Such coalsmay vary in size, water content, aromatic content, pre-treatment,cleaning, drying, and the like. Thus, certain process changes may bemade to accommodate the different coal types, including the kind ofhydrogen donor solvent used, amount of hydrogenation of the hydrogendonor solvent, increased hydrogenated material content, the amount ofrecycling of the CTD, the kind of coal used to generate the CTD,inclusion of catalysts, inclusion of hydrogen gas, inclusion ofadditional solvents or blends of hydrogen donor solvents, and the like.Variables related to the reactor include temperature, agitation,ultrasound, residence time, continuous processing, batch processing, andthe like. In the separation process, the speed of separation, duration,and the viscosity of the slurry may all be altered to yield modifiedtails and/or modified centrate. Referring to FIG. 8, in the distillationprocess, any of temperature, pressure, residence time, sparger use, airblowing, and gas flow rate may be varied to modify the distillationoutput, which can be any of gases, middle distillate, light distillate,pitches (e.g. binder-type pitch, impregnation pitch, graphite pitch,mesophase pitch, other pitches), and the like. The type of pitchobtained depends on the process variables and the coal extract, such asthe kind of coal used to generate the extract, the ash content, thesolvents used to liquefy the coal, and the like. Referring to FIG. 9,coke yields and types may be varied by changes in pressure, temperature,ramp rate, air blowing, residence time, coating of the coker, type ofcoke oven used (e.g. delayed coker, fluid coker, Flexicoker, beehiveoven, coke battery), and changes in starting pitch material, such as useof the any of the pitches described above in reference to FIG. 8.Depending in the input pitch and the process variables, possible cokeoutputs include graphite coke, needle coke, anode coke, anisotropiccoke, isotropic coke, shot coke, sponge coke, calcined coke, catalystcoke, fuel grade coke, and green coke.

The entire process may be controlled by a computer. The system mayinclude sensors and sensor feedback control to facilitate qualitycontrol and measurements. For example, sensors may be used to measurethe viscosity and temperature of the coal extract. When the sensordetermines the viscosity and temperature are suitable for separation,the sensors may send a signal to a processor that controls a valve or apump that facilitates transport of the coal extract from the reactor orholding tank to a separation unit, such as a centrifuge. In anotherexample, sensors may be used to control transport of coal to thereactor, transport of the centrate to the distillation column, transportof volatiles captured throughout the system to a tank, transport ofpitches distilled to a coker, and the like. Sensors may be used tomeasure the properties of the products of the process. Sensors may beused to provide realtime feedback during processing in order for anoperator of the system to make manual adjustments or for a processor tomake an automatic adjustment. Sensors may be used for safety purposes.

The methods and systems described herein may be deployed in part or inwhole through a machine that executes computer software, program codes,and/or instructions on a processor. The processor may be part of aserver, client, network infrastructure, mobile computing platform,stationary computing platform, or other computing platform. A processormay be any kind of computational or processing device capable ofexecuting program instructions, codes, binary instructions and the like.The processor may be or include a signal processor, digital processor,embedded processor, microprocessor or any variant such as a co-processor(math co-processor, graphic co-processor, communication co-processor andthe like) and the like that may directly or indirectly facilitateexecution of program code or program instructions stored thereon. Inaddition, the processor may enable execution of multiple programs,threads, and codes. The threads may be executed simultaneously toenhance the performance of the processor and to facilitate simultaneousoperations of the application. By way of implementation, methods,program codes, program instructions and the like described herein may beimplemented in one or more thread. The thread may spawn other threadsthat may have assigned priorities associated with them; the processormay execute these threads based on priority or any other order based oninstructions provided in the program code. The processor may includememory that stores methods, codes, instructions and programs asdescribed herein and elsewhere. The processor may access a storagemedium through an interface that may store methods, codes, andinstructions as described herein and elsewhere. The storage mediumassociated with the processor for storing methods, programs, codes,program instructions or other type of instructions capable of beingexecuted by the computing or processing device may include but may notbe limited to one or more of a CD-ROM, DVD, memory, hard disk, flashdrive, RAM, ROM, cache and the like.

A processor may include one or more cores that may enhance speed andperformance of a multiprocessor. In embodiments, the process may be adual core processor, quad core processors, other chip-levelmultiprocessor and the like that combine two or more independent cores(called a die).

The methods and systems described herein may be deployed in part or inwhole through a machine that executes computer software on a server,client, firewall, gateway, hub, router, or other such computer and/ornetworking hardware. The software program may be associated with aserver that may include a file server, print server, domain server,internet server, intranet server and other variants such as secondaryserver, host server, distributed server and the like. The server mayinclude one or more of memories, processors, computer readable media,storage media, ports (physical and virtual), communication devices, andinterfaces capable of accessing other servers, clients, machines, anddevices through a wired or a wireless medium, and the like. The methods,programs or codes as described herein and elsewhere may be executed bythe server. In addition, other devices required for execution of methodsas described in this application may be considered as a part of theinfrastructure associated with the server.

The server may provide an interface to other devices including, withoutlimitation, clients, other servers, printers, database servers, printservers, file servers, communication servers, distributed servers,social networks, and the like. Additionally, this coupling and/orconnection may facilitate remote execution of program across thenetwork. The networking of some or all of these devices may facilitateparallel processing of a program or method at one or more locationwithout deviating from the scope of the invention. In addition, any ofthe devices attached to the server through an interface may include atleast one storage medium capable of storing methods, programs, codeand/or instructions. A central repository may provide programinstructions to be executed on different devices. In thisimplementation, the remote repository may act as a storage medium forprogram code, instructions, and programs.

The software program may be associated with a client that may include afile client, print client, domain client, internet client, intranetclient and other variants such as secondary client, host client,distributed client and the like. The client may include one or more ofmemories, processors, computer readable media, storage media, ports(physical and virtual), communication devices, and interfaces capable ofaccessing other clients, servers, machines, and devices through a wiredor a wireless medium, and the like. The methods, programs or codes asdescribed herein and elsewhere may be executed by the client. Inaddition, other devices required for execution of methods as describedin this application may be considered as a part of the infrastructureassociated with the client.

The client may provide an interface to other devices including, withoutlimitation, servers, other clients, printers, database servers, printservers, file servers, communication servers, distributed servers andthe like. Additionally, this coupling and/or connection may facilitateremote execution of program across the network. The networking of someor all of these devices may facilitate parallel processing of a programor method at one or more location without deviating from the scope ofthe invention. In addition, any of the devices attached to the clientthrough an interface may include at least one storage medium capable ofstoring methods, programs, applications, code and/or instructions. Acentral repository may provide program instructions to be executed ondifferent devices. In this implementation, the remote repository may actas a storage medium for program code, instructions, and programs.

The methods and systems described herein may be deployed in part or inwhole through network infrastructures. The network infrastructure mayinclude elements such as computing devices, servers, routers, hubs,firewalls, clients, personal computers, communication devices, routingdevices and other active and passive devices, modules and/or componentsas known in the art. The computing and/or non-computing device(s)associated with the network infrastructure may include, apart from othercomponents, a storage medium such as flash memory, buffer, stack, RAM,ROM and the like. The processes, methods, program codes, instructionsdescribed herein and elsewhere may be executed by one or more of thenetwork infrastructural elements.

The methods, program codes, and instructions described herein andelsewhere may be implemented on a cellular network having multiplecells. The cellular network may either be frequency division multipleaccess (FDMA) network or code division multiple access (CDMA) network.The cellular network may include mobile devices, cell sites, basestations, repeaters, antennas, towers, and the like. The cell networkmay be a GSM, GPRS, 3G, EVDO, mesh, or other networks types.

The methods, programs codes, and instructions described herein andelsewhere may be implemented on or through mobile devices. The mobiledevices may include navigation devices, cell phones, mobile phones,mobile personal digital assistants, laptops, palmtops, netbooks, pagers,electronic books readers, music players and the like. These devices mayinclude, apart from other components, a storage medium such as a flashmemory, buffer, RAM, ROM and one or more computing devices. Thecomputing devices associated with mobile devices may be enabled toexecute program codes, methods, and instructions stored thereon.Alternatively, the mobile devices may be configured to executeinstructions in collaboration with other devices. The mobile devices maycommunicate with base stations interfaced with servers and configured toexecute program codes. The mobile devices may communicate on a peer topeer network, mesh network, or other communications network. The programcode may be stored on the storage medium associated with the server andexecuted by a computing device embedded within the server. The basestation may include a computing device and a storage medium. The storagedevice may store program codes and instructions executed by thecomputing devices associated with the base station.

The computer software, program codes, and/or instructions may be storedand/or accessed on machine readable media that may include: computercomponents, devices, and recording media that retain digital data usedfor computing for some interval of time; semiconductor storage known asrandom access memory (RAM); mass storage typically for more permanentstorage, such as optical discs, forms of magnetic storage like harddisks, tapes, drums, cards and other types; processor registers, cachememory, volatile memory, non-volatile memory; optical storage such asCD, DVD; removable media such as flash memory (e.g. USB sticks or keys),floppy disks, magnetic tape, paper tape, punch cards, standalone RAMdisks, Zip drives, removable mass storage, off-line, and the like; othercomputer memory such as dynamic memory, static memory, read/writestorage, mutable storage, read only, random access, sequential access,location addressable, file addressable, content addressable, networkattached storage, storage area network, bar codes, magnetic ink, and thelike.

The methods and systems described herein may transform physical and/oror intangible items from one state to another. The methods and systemsdescribed herein may also transform data representing physical and/orintangible items from one state to another.

The elements described and depicted herein, including in flow charts andblock diagrams throughout the figures, imply logical boundaries betweenthe elements. However, according to software or hardware engineeringpractices, the depicted elements and the functions thereof may beimplemented on machines through computer executable media having aprocessor capable of executing program instructions stored thereon as amonolithic software structure, as standalone software modules, or asmodules that employ external routines, code, services, and so forth, orany combination of these, and all such implementations may be within thescope of the present disclosure. Examples of such machines may include,but may not be limited to, personal digital assistants, laptops,personal computers, mobile phones, other handheld computing devices,medical equipment, wired or wireless communication devices, transducers,chips, calculators, satellites, tablet PCs, electronic books, gadgets,electronic devices, devices having artificial intelligence, computingdevices, networking equipments, servers, routers and the like.Furthermore, the elements depicted in the flow chart and block diagramsor any other logical component may be implemented on a machine capableof executing program instructions. Thus, while the foregoing drawingsand descriptions set forth functional aspects of the disclosed systems,no particular arrangement of software for implementing these functionalaspects should be inferred from these descriptions unless explicitlystated or otherwise clear from the context. Similarly, it will beappreciated that the various steps identified and described above may bevaried, and that the order of steps may be adapted to particularapplications of the techniques disclosed herein. All such variations andmodifications are intended to fall within the scope of this disclosure.As such, the depiction and/or description of an order for various stepsshould not be understood to require a particular order of execution forthose steps, unless required by a particular application, or explicitlystated or otherwise clear from the context.

The methods and/or processes described above, and steps thereof, may berealized in hardware, software or any combination of hardware andsoftware suitable for a particular application. The hardware may includea general purpose computer and/or dedicated computing device or specificcomputing device or particular aspect or component of a specificcomputing device. The processes may be realized in one or moremicroprocessors, microcontrollers, embedded microcontrollers,programmable digital signal processors or other programmable device,along with internal and/or external memory. The processes may also, orinstead, be embodied in an application specific integrated circuit, aprogrammable gate array, programmable array logic, or any other deviceor combination of devices that may be configured to process electronicsignals. It will further be appreciated that one or more of theprocesses may be realized as a computer executable code capable of beingexecuted on a machine readable medium.

The computer executable code may be created using a structuredprogramming language such as C, an object oriented programming languagesuch as C++, or any other high-level or low-level programming language(including assembly languages, hardware description languages, anddatabase programming languages and technologies) that may be stored,compiled or interpreted to run on one of the above devices, as well asheterogeneous combinations of processors, processor architectures, orcombinations of different hardware and software, or any other machinecapable of executing program instructions.

Thus, in one aspect, each method described above and combinationsthereof may be embodied in computer executable code that, when executingon one or more computing devices, performs the steps thereof. In anotheraspect, the methods may be embodied in systems that perform the stepsthereof, and may be distributed across devices in a number of ways, orall of the functionality may be integrated into a dedicated, standalonedevice or other hardware. In another aspect, the means for performingthe steps associated with the processes described above may include anyof the hardware and/or software described above. All such permutationsand combinations are intended to fall within the scope of the presentdisclosure.

While the invention has been disclosed in connection with the preferredembodiments shown and described in detail, various modifications andimprovements thereon will become readily apparent to those skilled inthe art. Accordingly, the spirit and scope of the present invention isnot to be limited by the foregoing examples, but is to be understood inthe broadest sense allowable by law.

All documents cited herein are hereby incorporated by reference.

1. A method of obtaining a de-ashed coal extract, comprising: exposing acoal to a sewage material in the presence of a coal-derived solvent toform a slurry; elevating the temperature of the slurry to facilitateliquefying the coal and liberating a volatile matter; and separating theinsoluble components from the slurry to obtain a de-ashed coal extract,wherein the coal extract is suitable for downstream processing.